Existing approaches to securely search databases or perform secure pattern matching fall short, because they are only secure under the honest-but-curious (HBC) model, and they can only perform exact matching. Schemes based on fully homomorphic encryption (FHE) are currently impractical to be implemented. For example, referring to the List of Incorporated Literature References, Literature Reference No. 4 describes only exact matching; Literature Reference No. 5 is impractical for streaming (i.e., requires linear bandwidth); Literature Reference No. 3 discloses only exact matching; and Literature Reference No. 2 is currently impractical because it requires high computational overhead.
Thus, a continuing need exists for a system that securely searches streaming data using multiple pattern matching modes and which only requires a constant amount of communication proportional to the pattern size being matched and independent of the data stream size.